Function Definition

A token identifying the interface within program​ containing the resource named name​.

name

The name of the resource to query the index of.

Description

glGetProgramResourceIndex returns the unsigned integer index assigned to a resource named name​ in the interface type programInterface​ of program object program​.

program​ must be the name of an existing program object. programInterface​ is the name of the interface within program​ which contains the resource named name​and must be one of the following values:

GL_UNIFORM

The query is targeted at the set of active uniforms within program​.

GL_UNIFORM_BLOCK

The query is targeted at the set of active uniform blocks within program​.

GL_PROGRAM_INPUT

The query is targeted at the set of active input variables used by the first shader stage of program​. If program​ contains multiple shader stages then input variables from any stage other than the first will not be enumerated.

GL_PROGRAM_OUTPUT

The query is targeted at the set of active output variables produced by the last shader stage of program​. If program​ contains multiple shader stages then output variables from any stage other than the last will not be enumerated.

The query is targeted at the set of active subroutine uniform variables used by the vertex, tessellation control, tessellation evaluation, geometry, fragment and compute shader stages of program​, respectively.

GL_TRANSFORM_FEEDBACK_VARYING

The query is targeted at the set of output variables from the last non-fragment stage of program​ that would be captured if transform feedback were active.

GL_BUFFER_VARIABLE

The query is targeted at the set of active buffer variables used by program​.

GL_SHADER_STORAGE_BLOCK

The query is targeted at the set of active shader storage blocks used by program​.

If name​ exactly matches the name string of one of the active resources for programInterface​, the index of the matched resource is returned. Additionally, if name​ would exactly match the name string of an active resource if "[0]" were appended to name​, the index of the matched resource is returned. Otherwise, name​ is considered not to be the name of an active resource, and GL_INVALID_INDEX is returned.

For the interface GL_TRANSFORM_FEEDBACK_VARYING, the value GL_INVALID_INDEX should be returned when querying the index assigned to the special names gl_NextBuffer​, gl_SkipComponents1​, gl_SkipComponents2​, gl_SkipComponents3​, or gl_SkipComponents4​.

Errors

GL_INVALID_ENUM is generated if programInterface​ is not one of the accepted interface types.

Although not an error, GL_INVALID_INDEX is returned if name​ is not the name of a resource within the interface identified by programInterface​.